The Influence of Simulated Service Exposure on the Rupture Strengths of Grade 11, Grade 22, and Type 304 Steels

1974 ◽  
Vol 96 (1) ◽  
pp. 10-21
Author(s):  
D. J. Wilson
Keyword(s):  
High Temperature ◽  
Present Stage ◽  
Time Service ◽  
Type Reaction ◽  
Stage Of Development ◽  
Straight Line ◽  
Long Time ◽  
Service Exposure ◽  
Type 304 ◽  
Grade 11

High temperature exposures were carried out to simulate long-time service. Rupture curves for exposed Grade 11 and Grade 22 steels did not exhibit the instabilities characteristic of the unused materials so that straight-line extrapolation gave good predictions of long-time strengths. Possibly due to a C-type reaction, strength predictions were poorer for Type 304 steel. Similar strengths were obtained using parameter tests of the unused materials. At the present stage of development, simulated service exposures offer an alternative, but not a superior, technique for extrapolating rupture characteristics.

Influence of Service Time on the Microstructure and High Temperature Mechanical Properties of T23 Boiler Tube

2017 ◽  
Vol 898 ◽  
pp. 711-718 ◽  
Author(s):  
Cheng He ◽  
Bao Liang Shi ◽  
Wen Sheng Li ◽  
Jian Ping Zhao ◽  
Kai Xu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
High Temperature ◽  
Service Time ◽  
Testing Machine ◽  
Tensile Testing Machine ◽  
Time Service ◽  
High Temperature Mechanical Properties ◽  
The Matrix ◽  
Long Time

The influence of long time service on the microstructure and high temperature mechanical properties of T23 steel was studied by optical microscopy, scanning electron microscopy, transmission electron microscopy and tensile testing machine. Results showed that lathy bainite ferrite disappears with the increasing service time, both the size and number of the carbides increases, and M23C6 carbides transform into M6C carbides rich in W element. The service process also has a significant influence on the recovery. Sub-grains were found at the grain boundaries with little dislocations in the matrix after 27448 h service time. After running for 27448 h the microstructure degradation of T23 steel is serious. High temperature tensile properties of T23 are closely related to the alloy aging degree. The reasons for the decrease of high temperature mechanical properties after long time service included microstructure degradations such as the increase of both the size and quantity of M23C6 carbides, the transformation of M23C6 to M6C, the desolution of Cr,W,and Mo elements, the decrease of the dislocation density and the occurrence of the sub-grains.

Microstructural characterization of plasma-processed Ti-Al metal matrix composites

1989 ◽  
Vol 47 ◽  
pp. 552-553
Author(s):  
M. G. Burke ◽  
M. N. Gungor ◽  
M. A. Burke
Keyword(s):  
High Temperature ◽  
Titanium Aluminide ◽  
Plasma Processing ◽  
Microstructural Characterization ◽  
High Temperature Strength ◽  
Matrix Composites ◽  
Intermetallic Matrix ◽  
Long Time ◽  
Strength And Stiffness ◽  
Intermetallic Matrix Composites

Intermetallic matrix composites are candidates for ultrahigh temperature service when light weight and high temperature strength and stiffness are required. Recent efforts to produce intermetallic matrix composites have focused on the titanium aluminide (TiAl) system with various ceramic reinforcements. In order to optimize the composition and processing of these composites it is necessary to evaluate the range of structures that can be produced in these materials and to identify the characteristics of the optimum structures. Normally, TiAl materials are difficult to process and, thus, examination of a suitable range of structures would not be feasible. However, plasma processing offers a novel method for producing composites from difficult to process component materials. By melting one or more of the component materials in a plasma and controlling deposition onto a cooled substrate, a range of structures can be produced and the method is highly suited to examining experimental composite systems. Moreover, because plasma processing involves rapid melting and very rapid cooling can be induced in the deposited composite, it is expected that processing method can avoid some of the problems, such as interfacial degradation, that are associated with the relatively long time, high temperature exposures that are induced by conventional processing methods.

Ecological aspects of modernization of alcohol industry enterprises at the present stage of development

2020 ◽  
Vol 5 (3) ◽  
pp. 179-184
Author(s):  
Marianna Havryshko ◽  
◽  
Olena Popovych ◽  
Halyna Yaremko ◽  
◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Food Industry ◽  
Ph Value ◽  
Negative Impact ◽  
Water Bodies ◽  
Raw Material ◽  
Present Stage ◽  
Alcohol Industry ◽  
Stage Of Development ◽  
World Industry

At the present stage of development, the entire world industry has faced the problem of rational use of renewable natural resources, in particular the most efficient ways of wastewater treatment and the use of accumulated waste in the production process as a secondary raw material. In particular, the alcohol industry, as one of the components of food, medical, chemical and various industries,leads to the formation of huge amounts of waste, including wastewater. The food industry, like any other industry, has a negative impact on the environment. Water bodies are the most affected by the food industry. Almost the first place in terms of water consumption per unit of production is the production of alcohol. Consumption of large amounts of water leads to the formation of wastewater, which is highly polluted and adversely affects the environment. Due to the high chemical and biological consumption of oxygen, specific color and odor, suspended solids, low pH value, the purification of such waste in the filtration fields and discharge into water bodies is not possible. The purpose of our work is: 1) conducting the analysis of the alcohol industry potential in Ukraine in recent years, and methods of waste disposal as a potential source for the development of bioenergy. 2) environmental aspects of the alcohol industry modernization at present stage of development and implementation of modern wastewater treatment technologies.

UNS N06455

Alloy Digest ◽  
1989 ◽  
Vol 38 (1) ◽  
Keyword(s):  
Corrosion Resistance ◽  
High Temperature ◽  
Stress Corrosion Cracking ◽  
Temperature Stability ◽  
Heat Treating ◽  
High Ductility ◽  
High Temperature Stability ◽  
Nickel Chromium ◽  
Long Time ◽  
Resistance To Stress

Abstract UNS NO6455 is a nickel-chromium-molybdenum alloy with outstanding high-temperature stability as shown by high ductility and corrosion resistance even after long-time aging in the range 1200-1900 F. The alloy also has excellent resistance to stress-corrosion cracking and to oxidizing atmospheres up to 1900 F. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Ni-367. Producer or source: Nickel and nickel alloy producers.

UNS R54620

Alloy Digest ◽  
1987 ◽  
Vol 36 (7) ◽  
Keyword(s):  
Titanium Alloy ◽  
High Temperature ◽  
Time Use ◽  
Temperature Stability ◽  
High Strength ◽  
Heat Treating ◽  
High Temperature Stability ◽  
Beta Titanium Alloy ◽  
Beta Titanium ◽  
Long Time

Abstract UNS No. R54620 is an alpha-beta titanium alloy. It has an excellent combination of tensile strength, creep strength, toughness and high-temperature stability that makes it suitable for service to 1050 F. It is recommended for use where high strength is required. It has outstanding advantages for long-time use at temperatures to 800 F. This datasheet provides information on composition, physical properties, elasticity, tensile properties, and bend strength as well as creep. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: Ti-86. Producer or source: Titanium alloy mills.

Formation of the research tradition of studying the institute Parliamentarism as a mechanism for the establishment of democracy

2017 ◽  
pp. 187-198
Author(s):  
Akil Ibrahim Al-Zuhari
Keyword(s):  
Balance Of Power ◽  
Research Strategy ◽  
The State ◽  
Executive Power ◽  
Research Tradition ◽  
Stage Of Development ◽  
The People ◽  
Long Time ◽  
The Government ◽  
Parliamentary Regimes

The article defines the features of the process of forming the research tradition of studying the institute of parliamentarism as a mechanism for the formation of democracy. It is established that parliamentarism acts as one of the varieties of the regime of functioning of the state, to which the independence of the representative body from the people is inherent, its actual primacy in the state mechanism, the division of functions between the legislative and executive branches of government, the responsibility and accountability of the government to the parliament. It is justified that, in addition to the regime that fully meets the stated requirements of classical parliamentarism, there are regimes that can be characterized as limited parliamentary regimes. The conclusions point out that parliamentarism does not necessarily lead to a democracy regime. At the first stage of development of statehood, it functions for a long time in the absence of many attributes of democracy, but at the present stage, without parliamentarism, democracy will be substantially limited. Modern researchers of parliamentarism recognize that this institution is undergoing changes with the development of the processes of democracy and democratization. This is what produces different approaches to its definition. However, most scientists under classical parliamentarianism understand such a system, which is based on the balance of power. This approach seeks to justify limiting the rights of parliament and strengthening executive power. Keywords: Parliamentarism, research strategy, theory of parliamentarism, types of parliamentarism

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